Walling stones can be laid in differing arrangements with very different results. Most commonly old walls tended to be built in either random coursed or random coursed with jumpers (jumper sneck) More modern building methods and stone production mean that more often new buildings are build in coursed walling stone.

Each example shown above can vary widely dependent upon the sizes of the stones making up the arrangement for example: One random coursed wall may consist of courses from 90mm to 110mm in height, another wall might have courses varying from 65mm to 250mm.

Jumpers.
This is a term for the stones laid in the vertical direction or larger stones that span more than one horizontal course. Sometimes Jumpers can be stones of a similar size to the rest of the wall, but often the larger stones are selected to use as the jumpers. Once again, this varies from one wall to the next.

Quoins.
This is a term used to describe the larger stones forming the corner blocks on the wall. These can range from smaller stones to huge blocks of stone, often regular shaped but sometimes irregular in size and shape. Quoins are seen on the corners of walls or buildings, also sometimes used for the edges of door and window openings.